Source: Fix various compiler warnings in Visual Studio 2017

Source/cmCPluginAPI.cxx

@@ -407,7 +407,7 @@ char CCONV* cmExpandVariablesInString(void* arg, const char* source,
   cmMakefile* mf = static_cast<cmMakefile*>(arg);
   std::string barf = source;
   std::string const& result =
-    mf->ExpandVariablesInString(barf, escapeQuotes, atOnly);
+    mf->ExpandVariablesInString(barf, escapeQuotes != 0, atOnly != 0);
   return strdup(result.c_str());
 }
 

Source/cmFileCommand.cxx

@@ -220,7 +220,7 @@ bool cmFileCommand::HandleWriteCommand(std::vector<std::string> const& args,
   // Set permissions to writable
   if (cmSystemTools::GetPermissions(fileName.c_str(), mode)) {
 #if defined(_MSC_VER) || defined(__MINGW32__)
-    writable = mode & S_IWRITE;
+    writable = (mode & S_IWRITE) != 0;
     mode_t newMode = mode | S_IWRITE;
 #else
     writable = mode & S_IWUSR;

Source/cmVisualStudioGeneratorOptions.cxx

@@ -269,7 +269,7 @@ void cmVisualStudioGeneratorOptions::FixManifestUACFlags()
 
     if (keyValue[1].front() == '\'' && keyValue[1].back() == '\'') {
       keyValue[1] =
-        keyValue[1].substr(1, std::max<int>(0, keyValue[1].size() - 2));
+        keyValue[1].substr(1, std::max(0, cm::isize(keyValue[1]) - 2));
     }
 
     if (keyValue[0] == "level") {

Source/cmWriteFileCommand.cxx

@@ -50,7 +50,7 @@ bool cmWriteFileCommand::InitialPass(std::vector<std::string> const& args,
   // Set permissions to writable
   if (cmSystemTools::GetPermissions(fileName.c_str(), mode)) {
 #if defined(_MSC_VER) || defined(__MINGW32__)
-    writable = mode & S_IWRITE;
+    writable = (mode & S_IWRITE) != 0;
     mode_t newMode = mode | S_IWRITE;
 #else
     writable = mode & S_IWUSR;